Although gene therapy was regarded as a promising approach for glioma treatment,its therapeutic efficacy was often disappointing because of the lack of efficient drug delivery systems.Mesenchymal stem cells(MSCs) have been reported to have a tropism for brain tumors and thus could be used as delivery vehicles for glioma therapy.Therefore,in this study,we attempted to treat glioma by using MSCs as a vehicle for delivering replication-competent adenovirus.We firstly compared the infectivity of type 3,type 5,and type 35 fiber-modified adenoviruses in MSCs.We also determined suitable adenovirus titer in vitro and then used this titer to analyze the ability of MSCs to deliver replication-competent adenovirus into glioma in vivo.Our results indicated that type 35 fiber-modified adenovirus showed higher infectivity than did naked type 3 or type 5 fiber-modified adenovirus.MSCs carrying replication-competent adenovirus significantly inhibited tumor growth in vivo compared with other control groups.In conclusion,MSCs are an effective vehicle that can successfully transport replication-competent adenovirus into glioma,making it a potential therapeutic strategy for treating malignant glioma. Although gene therapy was considered as a promising approach for glioma treatment, its therapeutic efficacy was often disappointing because of the lack of efficient drug delivery systems. Mesenchymal stem cells (MSCs) have been reported to have a tropism for brain tumors and therefore could be used as delivery vehicles for glioma therapy. Before, in this study, we attempted to treat glioma by using MSCs as a vehicle for delivering replication-competent adenovirus. We first compared the infectivity of type 3, type 5, and type 35 fiber-modified adenoviruses in MSCs.We also determined for adenovirus titer in vitro and then used this titer to analyze the ability of MSCs to deliver replication-competent adenovirus into glioma in vivo. Our results indicated that type 35 fiber-modified adenovirus showed higher infectivity than did naked type 3 or type 5 fiber-modified adenovirus. MSCs carrying replication-competent adenovirus significantly inhibited tumor growth in vivo compared with other control gr oups.In conclusion, MSCs are an effective vehicle that can successfully transport replication-competent adenovirus into glioma, making it a potential therapeutic strategy for treating malignant glioma.